Compass Sea Squirt

Asterocarpa humilis

Asterocarpa humilis is a sessile species of ascidian tunicate that can be found in subtropical and temperate regions, particularly in the Indo-Pacific, including Australia, New Zealand, Chile, and South Africa. It inhabits depths of up to 26 meters, often attaching itself to substrates in various marine environments. The species is characterized by its hermaphroditic nature, allowing it to reproduce through both cross- and self-fertilization. The reproductive process involves the development of eggs into lecithotrophic larvae, which eventually metamorphose into benthic adults. Divers may encounter the Compass Sea Squirt at various dive sites, where it often blends into the surrounding marine life. It can be distinguished from similar species by its unique morphology and habitat preferences. The animal typically resides in areas such as rocky reefs and piers, making it a common sight for divers exploring these environments. Its feeding mechanism involves filter-feeding, where it consumes plankton and other small particles from the water column. While the Compass Sea Squirt is not currently evaluated by the IUCN, its presence across multiple dive sites indicates a stable distribution within its habitat. Observing this species can provide insight into the health of the marine ecosystems it inhabits, as it plays a role in the broader ecological community.